在行動運算的環境裡，使用者通常都會使用行動裝置經由無線網路來存取遠端的檔案。然而，常常使用者會遇到一些網路的限制因而無法存取到遠端自己所需要的檔案，例如：防火牆、不穩定的網路狀況、網路斷線…等等惡劣的網路環境。一旦使用者遇到這些情況，他們可能會被迫停止手上目前的工作，直到他們能找到可使用的網路資源以及獲取所需的檔案為止。因此如果使用者擁有一個工具在網路環境良好的情況下，幫他們預先儲存未來可能會用到的檔案在行動裝置上，即使使用者在之後遇到這些惡劣的網路狀況，仍然可以在行動裝置上存取到自己想要的檔案。我們提出了一個複合式檔案貯藏方法，這個方法利用檔案區域性以及內容資訊來建立檔案彼此之間的關係，並利用這些資訊來預測使用者未來會使用的檔案進而預存重要的檔案。透過這樣檔案的預存機制，不但可以解決使用者處於惡劣的網路環境無法存取到遠端檔案的窘境，更能夠減少遠端傳輸所需要等待的時間和花費的資源 (如:電力消耗)。

In mobile computing environment, mobile users usually use their mobile devices to access remote data via wireless network. However, mobile users are unavoidable to face up the situation of network-related constraints such as firewall, weak connection, and even complete disconnection. Once mobile users are in these surroundings, they might not access the necessary remote data and be forced to postpone their jobs. Therefore, it is critical for mobile users to have an automatic file hoarding scheme to preload necessary data into local storage before disconnected from the networks. We propose a hybrid file hoarding scheme to assist mobile users to load the files that the users might need in disconnected mode. The hybrid file hoarding scheme combines file locality and content information to predict the file set used during disconnections. The hybrid file hoarding scheme not only help users to access remote data in disconnected mode but also reduce access latency and transmission costs of remote access via the networks.

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